This invention relates to a supplemental restraint assembly for an automotive vehicle and more particularly to a self-tensioning side impact air bag assembly.
Air bags mounted in an instrument panel or steering wheel to protect an occupant from a front impact have become standard in the automotive industry. Numerous variations of these air bags, deployment systems and housing devices have evolved over the years. However, these frontal air bags do not provide protection to the occupant during a side impact. Recent developments have focussed on technology directed to side impact air bags and related systems.
Side impact air bag systems are also known in the art. These side impact air bags are often mounted adjacent the vehicle""s roof rail, doorframe or center pillars, or in some instances within the side door. It is desirable to have tensioning to position the bag during side impact as well as any secondary events.
FIGS. 7A and 7B depict a side impact air bag 1 of the related art. The air bag 1 has a top edge 3 and a lower edge 4. A front tether 5 and rear tether 6 connects the inflatable element 2 to corresponding front and rear pillars of an automotive vehicle. The top edge 3 has a plurality of mounting connections 7 for connection to the vehicle""s roof rail. The air bag 1 may have a plurality of straight substantially square zero length tethers 8 extending from the lower edge 4 to the top edge 3. FIG. 6B depicts the air bag of FIG. 6A in an inflated state. The inflatable element 2 shrinks when inflated and induces tension in the lower edge 4 and the tethers 5, 6. This tension tends to hold the air bag 1 in place relative to the vehicle. However, the amount that the lower edge 4 may constrict is limited and therefore, the amount of tension and take up in the tethers 5,6 is limited to the amount that the lower edge 4 constricts during inflation.
It is an object of the invention to provide an improved supplemental restraint assembly that improves upon the related art.
The present invention is directed to a side impact air bag with a self-tensioning tether/lace interlaced within the side air bag. A side air bag is secured to the vehicle along the roof rail between the front and rear pillars. A tether or lace is secured to the air bag and traverses a plurality of predetermined guide points. When the side impact air bag is inflated the distance between the guide points increases and any slack in the tether/lace is taken up. Thus the air bag is securely held in place when deployed. The side impact airbag, under some circumstances, serves to mitigate the threat of an occupant being ejected during a roll over event or subsequent impact.